Earth tamper



Dec. 11, 1962 Filed June 21, 1957 5K. R. WIEKHORST 3,067,657

EARTH TAMPER 3 SheetsSheet 2 g 1962 K. R. WlEKHORSTi 3,067,657

EARTH TAMPER Filed June 21, 1957 3 Sheets-Sheet 3 K WW. INVENTOR.

Unite 3,067,657 EARTH TAMPER Kenneth R. Wiehhorst, 38492 S. 70th St., Omaha,Nebr. Filed June 21, 1957, Set. No. 667,082 3 Claims. (Cl. 94-49) This invention relates to earth .tamping and it is an object of the invention to provide an earth tamper particularly adapted for use on a mobile crane.

Heretofore the tamping of the earth in the bottom of ditches has been done almost entirely by air hammers, each held in the hand of an operator. To a limited ex tent hydraulically operated mobile tamping machines have been used. However hydraulic tamping machines have had the disadvantage that the vehicle part thereof cannot be driven sufiiciently close to a wall so as to tamp close to the wall where tamping is vitally needed.

A particular object is to provide a tamping machine having a guide portion which is suspended from the *boom of a crane and further having a tamping hammer vertically slidable in the guide portion, the hammer also being suspended from the crane independently of the guide portion and in which the guide portion has a flat side which can slide along the relatively fiat side of a ditch to guide the hammer from one tamping position to a new tamping position, the flat side also serving to guide the hammer as it slides along the side of a wall of a building, thus being distinguished from pile-driver guide housings which latter are cylindrical and without a flat side.

A further object is to provide a tamper the hammer portion of which is rectangular for tamping a rectangular pattern on the earth whereby successive tampings need not overlap, or can overlap very little, in order to gain a completion of tamping. This cannot be done with a cylindrical pile-driver hammer because a circle makes complete tamping practically impossible. When one circle tamped is overlapped with another circular area tamped, there is always a somewhat triangular space between that remains untamped. Placing tamped circles in a pattern almost completely overlapping makes waste of tamping strokes and great ineificiency.

Comparison with a pile-driver is made here only because it is the only similar machine in existence. Piledrivers have never been used for tamping to my knowledge and there is a second reason why pile-drivers could never be effectively used for tamping. This second reason is that a pile-driver housing is normally completely closed, a completely closed cylinder. In-my experiments I have found that a completely closed housing will not work for tamping. In tamping, dirt is brought up with the hammer and a closed housing becomes clogged. It is, therefore, an object of my invention to provide my discovery of the concept of an open housing making a self-cleaning machine.

A further object of the invention is to provide a tamper with a rectangular guide housing and a rectangular hammer whereby the housing has sides of two different sizes as is of advantage as the narrow dimension can be used for tamping a narrow ditch and the longer dimension can be used for tamping a wider ditch.

A particular object is to provide a tamping machine that is adapted to tamp along a building wall, along the square corners of a building, in trenches, and along a concrete wall.

A further disadvantage in the use of such tampers is that they are only adapted to tamp to a certain limited depth.

It is also an object of my invention to provide a tamping machine which can tamp to any depth desired without limit, through the provision of'suspension cables for the 3,057,657 Patented Dec. 11, 1962 2 tamping and guide mechanisms which can be of any suitable length.

A further object of my invention is to provide a mobile tamper which is adapted to tamp at all places around an excavation.

Mobile tampers of the prior art can only tamp effectively where the ground is level. It is therefore an object of my invention to provide a tamper which, through the use of a long boom, makes possible tamping in almost any situation, even though the ground he so uneven that the crane itself cannot enter.

Certain mobile tampers of the prior art are suitable only for use in tamping an excavation in a roadway and tamping strokes would be thrown entirely out of alignment if the machine were used to tamp the type of a ditch having excavated earth piled up around it which would be under the wheels of the machine throwing the tamping stroke out of desired positions.

Machines of the prior art which are called hydrohammers and which are used in some types of tamping, are unable to straddle a Wide ditch, and so, being limited by the straddle principle, are unsuitable for tamping wide ditches. It is therefore an object of my invention to provide a tamper which will work in wide ditches, and such that if the ditch is so wide that the new machine cannot tamp from twosides, then the machine itself can go down the center of the ditch.

A particular object of the invention is to provide a tamper which is adapted to be used on any type of crane, whereby in the use of my tamper assembly it is unnecessary for a contractor already having cranes to make extra investment in a tamping vehicle.

A further object of the invention is to provide a tamping assembly, the tamping force of which can be easily varied and controlled as needed, so as, for example, not to break sewer tile or the like in the bottom of the ditch being tamped.

An object of my invention is to provide a tamping assembly, the tamping stroke of which is easily directed through the use of a guide portion which effectively guides the hammer to a selected impacting position without danger of the hammer swinging in a fashion such that it might ram and break a wall or cave in the banks of a ditch.

I am aware of the C. N. Friz patent, No. 1,650,827, issued November 29, 1927, titled Method of Compacting Earth, in which a rectangular hammer is carried in a guide. However, as the guide is not suspended, this diifers from my concept. Also, as the Friz guide is not used below the ground as are certain Friz earth segregating open-sided boxes, the concept of the low ground use of a guide such as is my invention is not present in Friz.

My concept is that the guide be free to shift and not be attached to anything below ground as the Friz guide 22 of FIGURE 2 is so attached to his earth-segregating opensided box 17.

A further objective is to provide a tamping machine which is very easily controlled whereby it is possible for it to eifectively tamp a ditch of any width becaues of the control the operator has regardless of whether or not the ditch be of a width far greater than the width of the guide portion of the tamper.

A further object is to provide an earth tamping assembly having a plurality of interchangeable hammers, each having heads designed for purposes such as demolition work wherein the assembly may be used in breaking concrete, cutting asphalt and other pavement, cutting trenches in pavement or roads, crushing rock and tamping each fill.

Other'and further objects and advantages of the present invention will be apparent from the following detailed description, drawings and claims, the scope of the invention not being limited to the drawings themselves as the drawings are only for the purpose of illustrating a way in which the principles of this invention can be applied.

Other embodiments of the invention utilizing the same or equivalent principles may be used and structural changes may be made as desired by those skilled in the art without departing from the present invention and the purview of the appended claims.

In the drawings:

FIGURE 1 is a perspective view of the earth tamper of this invention shown attached to a portable crane in operating position;

FIGURE 2 is an elevational view of the device as it would appear in position for tamping earth fill in a trench; the trench being shown in cross section;

FIGURE 3 is an elevational view of the device as it would appear in position for tamping earth fill adjacent a foundation wall, building wall or the like;

FIGURE 4 is an isometric View of the tamper or hammer portion of the device;

FIGURE 5 is an enlarged elevational view of the device constituting this invention, some parts broken away for convenience of illustration;

FIGURE 6 is an enlarged top plan view of the device shown in FIGURE 5;

FIGURE 7 is an enlarged horizontal cross sectional view taken along the line 77 of FIGURE 5;

FIGURE 8 is a fragmentary longitudinal cross section taken along the line 88 of FIGURE 5 FIGURE 9 is a fragmentary elevational view of a modified hammer having a transversely disposed vertical cutting blade secured to the bottom thereof;

FIGURE 10 is a fragmentary side elevational view of the modified hammer of FIGURE 9 showing an end elevation of the cutting blade; and

FIGURE 11 is a perspective view of a further modified hammer; such modified hammer having a rounded rock breaking head portion positioned at the lower end thereof.

Referring now to the drawings in detail, like reference numerals refer to like parts through out the several views.

The numeral 11 designates the earth tamper of my invention in its entirety which generally comprises a guide 12 associated with a movable hammer 14 axially disposed therein; the guide 12 serving to maintain directional movement of the hammer 14 throughout its length of travel.

The guide 12 is of an elongated, open frame-work construction being rectangularly shaped as seen in top plan view. Four elongated angle iron members form upright corner posts 21 of the guide 12, the angle facing inwardly.

The four corner posts are arranged in spaced apart parallelism and secured together by a plurality of transversely disposed side plates 22 and 24. The side plates 22 and 24 are of elongated rectangular shape being positioned one at the upper end, one at the lower end and a pair disposed in spaced apart relation therebetween. The plates 22 and 24- have their ends suitably secured, preferably by welding, to the outwardly facing surfaces of the flange of the angle iron corner posts 20.

It will be seen that the plates 22 on opposing sides of the guide 12 are of greater length than the opposed side plates 24 whereby the guide 12 is of oblong rectangular shape in top plan view for reasons which will be explained later.

As thus described it will be seen, with reference to FIGURE 1, that the side plates 22 and 24, being aligned and joined at their ends in construction appear as continuous bands extending about the corner posts 20 in spaced relation longitudinally of the guide and serve not only to tie in the corner posts 20 but also serve as torsional bracing for the guide 12. Although I show four side plates to a side of the guide 12 it will be understood that any desirable number of plates may be employed dependent upon the overall size and length of guide desired.

The lower end of the guide 12 is open and to further provide rigidity and strength, I employ triangularly shaped gusset plates 26, a pair at each corner, being welded or otherwise suitably fixed to the flange of a respective corner post 20 and adjacent upper edge of the respective side plates 22 or 24.

A flat plate closes the upper end of the guide 12 and will hereinafter be referred to as the top or top plate 28. The edges of the top plate 28 are flush with the side surfaces of the upper ones of the side plates 22 and 24 and is welded in place, thus forming a full cap at the top of the guide 12.

Referring to FIGURE 6 it will be seen that in top plan view the guide, as mentioned, is of rectangular shape and therefore the top plate 28 shall be hereinafter referred to as having a length and width for simplicity of description.

An upwardly projecting rib or flange 311 is disposed across the width of the top plate 28 from one side to the other at a point midway between its ends. Two pair of triangularly shaped gussets 32 are disposed on either side of the flange 30 near the ends thereof; being preferably welded to the sides of the flange 30 and the upper surface of the top plate 28 respectively.

An aperture or eye 34 is provided extending through the flange 30 at a point centered between its ends. In practice, my guide 12 is secured to a suitable carrier. In accordance with my conception the guide 12 is attached to a mobile crane, generally indicated by the numeral 40 and more particularly is suspended from the upper end of the boom 42 thereof by means of a flexible lift cable 44. The free end of the cable 44- is inserted through the eye 34. The cable end may then be secured to the standing part as shown at 46, or in any other conventional manner.

The cable 44 is run over a sheave 48 mounted at the upper end of the boom 42 and then extends downwardly on the rearward side of the boom 42 and is secured to suitable mechanism for raising or lowering the guide 12 located within the crane 40 and controllable by the operator from his position in the cab 50 of the crane 40.

The hammer 14, as illustrated, is of a length approximately one-third of the total length of the guide 12 and is of box-like open-frame construction similar to the guide 12. The hammer 14 is adapted for slidable movement within the guide 12. The hammer assembly comprises four elongated angle iron corner posts 52 having interconnecting spaced apart transversely disposed side plates, a first set 54 and 56 being secured at the upper end of the hammer assembly and a second set 58 and 66 secured to the corner posts 52 at points a substantial distance therebelow.

The lower end of the hammer 14 is provided with a weight box, generally indicated by numeral 62, formed of side walls 64 and 66 which are similarly arranged and secured in comparison to the side plates 54-6tl but have a greater width.

The lower end of the hammer assembly or Weight cage is covered or closed by an impact plate 68 which is suitably secured to the ends of the corner posts 52 and lower edges of the weight box side walls 64 and 66 thus forming the bottom wall of the weight box 62.

The side plates and weight box side walls are of such length with respect to the corner posts 52 thereof to provide a rectangular shape in top plan view complemental to the inner dimensions of the guide 12.

With reference to FIGURE 4, it will be seen that the ends of the Weight box side walls 64 and 66 and the side plates 54-60 are joined and secured to the corner posts 52 within the angle thereof. As thus described, it will be seen that the outer surfaces of the corner post flanges are free from obstruction whereby, in assembly, they are disposed in close relationship with the inner surfaces of the angle of the corner posts 20 of the guide 12. As thus described, the guide corner posts 20 act as trackways for the coner posts 52 of the hammer assembly 14 which may be likened to track followers.

Returning now to the hammer construction, an elongated plate 70 is axially disposed within the hammer assembly having its lower end secured to the upper surface of the impact plate 68 and suitably braced by short lengths of angle iron 72 extending transversely of the lower end. The angle iron braces 72 are secured to a side surface of the lower end of the-plate 7G and the upper surface of the impact plate 68 respectively.

The vertically disposed plate 70 extends upwardly and its upper end terminates a substantial distance beyond the upper edge of any one of the side plates 58 or-fitl as best seen in side elevation in FIGURE 5.

Bracing struts 74 and 76 are provided at the upper end of the plate '76 and comprise a pair of struts 74 disposed transversely of the plate 70 one on either side of the upper end thereof and which are secured to the plate side surfaces. The ends of the struts 74 are preferably welded to the inner surfaces of the respective opposed side plates 58.

Further struts 76 are disposed at right angles to the struts 74 having their inner ends secured to the outer surface of the respective strut 74 and their outer ends seedges; their outer edges being flush with the side walls 64 and 66. The closure plates 80 and 82 are suitably secured preferably by welding.

A plurality of triangular gusset plates 84 are provided through the central portion of the hammer assembly, a

pair being disposed secured on either side edge of each corner post 52 and the respective upper edge of the side plates 58 and 60. The gussets 84 add to the strength and torsional rigidity of the hammer assembly 14.

As best seen in FIGURES 1 and the hammer 14 is shown in operative position within the guide 12 and particularly in FTGURE 5 the close slidable relation of the corner posts 52 of the hammer assembly 14 within the angle of the corner posts of the guide 12 may be seen.

The crane has a further cable 90 the free end of which extends downwardly through a cable opening 92 provided in the top plate 28 adjacent a side of the flange 30 and is then inserted through an aperture or eye 94 extending through the upper end of the plate of the hammer assembly at a point intermediate of its width. The cable end may then be secured to the standing part as shown at 96, or in any other conventional manner.

The cable 90 is run over a second sheave 98 mounted in the upper end of the boom 42 which is laterally spaced from and in alignment with the sheave 48. The cable 91} then extends downwardly on the rearward side of the boom 42 to connect with suitable mechanism on the crane 49 for hoisting the hammer 14 to an elevated position within the guide 12 and for releasing the cable 9% permitting the hammer to fall freely under the influence of gravity.

Referring to FIGURE 6, I further provide a pair of rollers 1% disposed in spaced apart parallel positions longitudinally and rotatably secured to the top plate 28, one on each side of the cable opening 92.

The rollers 1d!) are journaled about and freely rotate upon shafts 102 which have their inner ends extending through suitable apertures in the flange 3t and their outer ends supported in an upwardly extending shaft support or spacer flange 1%. The shaft support flange 104 is suitably secured to the upper surface of the top plate 2% in parallelism with the flange 39 whereby the rollers '6 latter is secured to the flange 30 by means of a cap screw 110.

The outer ends of the shafts 102 are each provided with grease fittings 112 for permitting lubrication of the rollers 100.

A like arrangement of rollers 114 are disposed on the underside of the top plate 23 adjacent the cable opening 92; being journaled about shafts 11S supported in spaced apart downwardly extending shaft support flanges 120 attached to the under surface of the plate 23. The shafts 118 are provided with a lock key 122 at one end which is secured to the respective support flange 120 by a cap screw 124. The opposite end of the shafts 118 are provided with grease fittings 126 for lubrication of the rollers 114.

With reference to FIGURES 6 and 7, it will be seen that the rollers 114 on the under side of the top plate 28 are arranged at right angles to the axis of the rollers 1110 mounted on the upper surface of the top plate 28. Further, that the innermost side surface of each roller overlaps the respective side edge of the cable opening 92 'a substantial distance. As thus described, it Will be seen that the rollers 16% and 114 being arranged at right angles to each other and overlapping the side edge of the cable opening 92 guard against any bending or binding of the cable 91) around a sharp edge. The rollers 100 and 114 further prevent excessive Wear of the cable which would result if the cable 911 were allowed to kink and chafe against the edges of the opening 92 during hoisting and release of the hammers 14.

Means are provided for limiting the upward travel of the hammer within the guide comprising stops 131} which are disposed at the uppermost end of each of the guide corner posts 20, as best seen in FIGURES 7 and 8. More particularly the stops are L shaped in elevation being fitted within the angle of the corner posts 20 and welded in place.

The normally horizontally disposed base leg of the stop is disposed a substantial distanw below the under surface of the plate 28 and provides a bumper 132 which is abutted by the uppermost ends of the corner posts 52 of the hammer assembly 14 should the operator hoist the hammer beyond reasonable upper limits. The stops further guard against the hammer making direct contact with the top plate 28 and prevents excessive bending of the hammer lift cable 9% when the hammer 14 is hoisted to its uppermost position.

The guide 12 is further provided with tag line attachment members 134 disposed at each corner of the upper surface of the top plate 28.

The tag line attachment members 134 are L shaped in side elevation having a normally horizontally disposed base leg 136 and an upwardly extending ear portion 138 which latter has an aperture or eye 141 therein. As best seen in FTGURE 6 the members 134 are diagonally disposed across each corner of the top plate 28.

The crane as is further equipped with suitable mechanism, generally indicated by the numeral 142, for playing out and automatically reeling in slack on a tag line 144. The tag line 1 14 has one end thereof secured to and wound about a drum of the mechanism. The free end of the tag line 1454 is inserted through the eye 1% of a selected one of the members 134, the line or cable end being secured by suitable means such as shown at 148, or in any other suitable manner.

With reference to FTGURE 1, it will be seen that the tag line mechanism 142 is mounted on the boom 42, a substantially distance below the free end thereof. The tag line 144 serves to maintain the guide 12 in proper operating position with respect to the position of the crane 4d and the area being tampered.

The tag line 14-dprevents rotation of the suspended guide 12 to guard against twisting and chafing of the lift cables 44 and 90.

In operation, the boom 42 is swung'into-position to '7 bring the tamping assembly directly over the area to be tamped where the guide 12 may be lowered so that its lower end is in contact with the ground yet leaving sufficient tension on the cable 44- to maintain the guide 12 in an upright position. The operator then actuates the mechanism for winding up the hammer lift cable 90 to raise the hammer 14 to its uppermost position within the guide whereupon the cable 91) is released and the hammer drops forcibly. The earth fill therebelow is compacted by the weight of the hammer 14.

Successive movement of the boom 42 and actuation of the hammer 14 progressively tainps the desired area. It will be seen that the guide 12 prevents lateral displacement of the hammer impact and when the hammer is in its lowermost position substantially all of its length remains within the guide to maintain substantially uniform strength throughout the length of the guide 12 against lateral thrust.

FIGURE 1 illustrates the invention in operative position when tamping an area substantially at ground level. However, my invention is of a particular design most advantageous in tamping back-fill in trenches, as shown in FIGURE 2, and in operation closely adjacent a building wall or the like, as illustrated in FIGURE 3.

Referring to FIGURE 2, the tamping assembly is shown in operation in a trench 150 whereby the operator lowers the guide 12 into the trench 150. The lower end of the guide extends into the trench 150 and the side walls of the trench 150 serve as guides to maintain the position of the guide 12 above the back-fill and the hammer 14 will securely tamp the back-fill 152 upon successive lift and release thereof as the operator moves the device progressively down the trench 150.

The difference in side dimensions of the device, the assembly being rectangularly shaped in top plan view, is important at this stage. There appears to be at present, two standard widths of mechanically excavated trenches and, therefore, it is my conception that the outer dimensions of the guide 12 be such that the guide may be readily and closely received between the side walls of a trench of particular width by selectively adjusting the guide 12 rotatably with respect to the width of its sides. The guide is then maintained in proper position by the attachment of the tag line 144 in combination with the guiding action of the side Walls of the trench.

FIGURE 3 illustrates the effectiveness of the device in operation closely adjacent a building wall 154. The danger of the hammer striking the wall is eliminated since the guide 12 maintains the Vertical movement of the hammer 14 throughout its entire length of travel.

it will further be understood that the compression force of the hammer 14 is variable dependent upon the distance of free fall allowed the hammer 14 by the operator.

Although my invention is primarily concerned with earth tamping wherein a hammer having a flat impact plate is employed, it is further my conception that the device may be used for other purposes such as demolition QIK by employing modified hammer assemblies.

For example, a modified hammer may be used for the purpose of cutting through asphalt pavement or the like and one embodiment of such a hammer is shown in FIG- URES 9 and wherein the hammer assembly is much the same as above described but for the addition of an elongated, downwardly extending blade 160 disposed transversely of and secured to the under surface of the .impact plate 68. The blade has a sharp cutting edge 162.

The remainder of the under-surface of the plate 68 is *covered with a thick pad or cushion 164, preferably of rubber, suitably secured thereto.

The cushion 164 protects the area of the pavement surrounding the cut from serious damage during operation by placing a shock absorbing means between the weight of the hammer and the surface of the pavement.

A further modification of a hammer assembly is shown F UR 11 w ere n a rock breaking head 168 is 8 substituted for the weight box 62 and impact plate 68. The rock breaking head 168 has a rounded face 170 and would be useful in reducing large rock to movable size, crushing rock for leveling and demolishing pavement to be removed and the like.

The operation of the device employing these modified hammers is substantially the same as the operation of the earth tamping assembly above described.

From the foregoing description it is thought to be obvious that an earth tamper constructed in accordance with my invention is particularly Well adapted for use, by reason of the convenience and facility with which it may be assemble-d and operated, and it will also be obvious that my invention is susceptible of some change and modification without departing from the principles and spirit thereof, and for this reason I do not wish to be understood as limiting myself to the precise arrangement and formation of the several parts herein shown in carrying out my invention in practice, except as claimed.

I claim:

1. In a tamping machine, the combination which comprises an elongated vertically disposed guide frame including angle iron corner posts connected by transversely disposed side plates providing a track and having a flange extended from the upper end for attaching a cable to said guide frame, a weight cage slidab-ly mounted in the guide frame and including corner angle irons connected by upper and lower sets of side plates and an impact plate secured to lower ends of the corner angle irons and extended across the cage, the side and impact plates at the lower end of the weight cage providing a container for heavy material whereby upon being filled with concrete or the like the container provides a weight, and a vertically disposed plate secured to the impact plate by angle irons and extended from said impact plate upwardly to a point spaced above the lower set of side plates, the upper end of said vertically disposed plate having a cable receiving opening therein.

2. In a tamping machine, the combination which comprises an elongated vertically disposed guide frame including angle iron corner posts connected by upper, lower, and intermediate transversely disposed side plates, the corner posts providing a track, a cable attaching flange extended upwardly from the upper end of the frame, and cable guiding means in the upper end of the guide frame, and a weight cage having angle iron corner posts connected by side plates and positioned whereby said corner posts'of the weight cage slide vertically in the corner posts of the guide frame, an impact plate extended across and secured to lower ends of the corner posts of the weight cage, a vertically disposed plate secured to said impact plate and extended upwardly to a point above lower side plates of the weight cage, the side and impact plates at the lower end of the weight frame providing a concrete holding box, and the intermediate part of the weight cage being provided with a cable attaching plate assembly.

3. In a tamper, the combination which comprises an elongated vertically disposed guide frame, rectangularshaped in cross section, and having angle iron corner posts connected by upper, lower, and intermediate transversely disposed side plates providing a track, a horizontally disposed plate having an opening therethrough mounted on upper ends of the posts, a cable attaching flange extended upwardly from said plate, spaced longitudinally disposed rollers rotatably mounted on said plate, and positioned to register with the opening therein spaced transversely disposed rollers rotatably mounted on and suspended below the opening in said plate, a weight cage having angle iron corner posts slidably mounted in the corner posts of the guide frame, side plates connecting the corner posts of the weight cage and positioned at upper and lower ends and at a point intermediate of said upper and lower ends of the corner posts, of the cage an impact plate connecting lower ends of the posts of the weight cage, the side plates at the lower end of the weight cage and impact plate providing a container for concrete to form a weight, and cable attaching elements in the upper portion of the weight cage, a cable for suspending the weight cage being extended between the longitudinally disposed rollers and also between the transversely disposed rollers carried by the horizontally disposed plate.

References Cited in the file of this patent UNITED STATES PATENTS 10 Friz Nov. 29, 1927 McNeilly Dec. 5, 1933 Ruddock July 18, 1939 Porter Mar. 11, 1941 Pegno Dec. 15, 1942 Gedge May 30, 1944 Lichtenberg Aug. 22, 1944 Scheidt Feb. 26, 1957 FOREIGN PATENTS Germany June 17, 1902 Germany Aug. 16, 1933 

